Multivariate discrimination,tooth measurements and early hominid taxonomy

It is argued that the value of the various multivariate approaches in dealing with functional, taxonomic, and phylogenetic problems can only be determined empirically. A review of three studies dealing with multivariate analyses of the early hominid dentition suggests that at best, the multivariate statistics used are inappropriate and the results contradictory.     

New and poorly known Cenozoic clown beetle compressions from France (Insecta: Coleoptera: Histeridae)

Summary

Two French fossil Histeridae are described or revised, viz. Hister cerestensis n. sp. from the Oligocene of Céreste (Lubéron) and Plegaderus pitoni (Theobald, 1935), n. comb. from the Pliocene of Chambon Lake (Puy-de-Dôme). Morphometric data are used to compare fossil and extant taxa, with multivariate statistics. A list of the fossil Histeridae is given.     

Multivariate analysis in biological anthropology: Some considerations

The relation between modern multivariate statistical analysis and common objectives in biological anthropology is discussed. Many formal statistical assumptions should be satisfied to fully justify multi-variate analysis, but rarely are. Their failure does not have as adverse an effect upon scientific research as some procedural errors in research design. These include the treatment of single specimens as if they are samples, and the failure to separate considerations of size and shape. The superiority of elaborate multivariate distances over simpler quantitative techniques, inferred from the former's consideration of trait intercorrelations, is unwarranted from both theoretical and practical aspects. Based on these points and several comparative examples of analyses, it is argued that simpler, non-statistical approaches such as those of the school of numerical taxonomy have much to offer primato-logical studies. Classic multivariate statistics, while useful for studying closely similar living populations, are considerably more limited in usefulness and significance for paleoanthropological studies.     

Multivariate analyses of metrical features in the Lepidapedon elongatum (Lebour, 1908) species-complex (Digenea,Lepocreadiidae) in deep and shallow water gadiform fishes of the NE Atlantic

One hundred and eleven Lepidapedon elongatum-like worms from five gadiform fish species in the North Atlantic are compared using multivariate analyses of 22 metrical features. A principal component analysis followed by a discriminant analysis indicate multivariate morphological differences between worms in the different hosts. It is argued that the forms in the five host species, Gadus morhua, Onogadus argentatus, Trachyrhynchus trachyrhynchus, Coryphaenoides (Nematonurus) armatus and Lepidion eques, should be considered separate oioxenic species.     

The Great Bend Aspect: A Multivariate Investigation Of Its Origins And Southern Plains Relationships

Abstract

The origins of the Great Bend aspect as well as its relations with a series of southern Plains sites are analyzed using ceramic attributes and multivariate statistics. Although the data is inadequate in certain areas the results suggest that in-situ development from earlier cultural groups is a more likely explanation than is a migration of peoples from the southern Plains.     

Anti-Semitism in Britain: continuity and the absence of a resurgence?

Abstract

It has become the orthodoxy in recent years to assume that anti-Semitism globally is not only rising but also taking a new form – it is a ‘new anti-Semitism’ or even a new phenomenon: Judeophobia. This article takes a different perspective. It initially covers approaches to anti-Semitism and how, especially in the light of the Holocaust, it has been viewed academically as no longer the fault of the Jews but as a natural and constant feature of history since antiquity. A critique is provided of the idea of a continuous history of anti-Semitism and of the metaphors used to describe it. There then follows a case study of anti-Semitism in Britain. The British case is valuable as it is seen as a key example of the ‘new anti-Semitism’, and one that is more striking given the alleged absence of previous hostility towards Jews in that country. By employing a comparative approach – both temporal and in relation to responses to other groups – change and continuity are charted through a study of racial violence. Such comparisons, it is argued, allow a more nuanced and balanced analysis of this issue, which has created much alarm and little sober reflection.     

An Alternative View of Some Southern Plains Archaic Stage Characteristics

Abstract

It is argued that Hammatt’s 1976 review of the Southern Plains Archaic Stage is in part not well reasoned or well supported. His contention that projectile point styles are not reliable as indicators of Archaic sites, while Clear Fork gouges are, is unsupportable and logically inconsistent based on the data he used. Other attributes used by Hammatt to define Archaic components are also discussed. Hammatt views the study of subsistence patterns (adaptation) rather than projectile points, as a more meaningful way to identify Archaic sites. This is a welcome argument and goal     

Cognition of and Demand for Education and Teaching in Medical Statistics in China: A Systematic Review and Meta-Analysis

BackgroundAlthough a substantial number of studies focus on the teaching and application of medical statistics in China, few studies comprehensively evaluate the recognition of and demand for medical statistics. In addition, the results of these various studies differ and are insufficiently comprehensive and systematic.ObjectivesThis investigation aimed to evaluate the general cognition of and demand for medical statistics by undergraduates, graduates, and medical staff in China.MethodsWe performed a comprehensive database search related to the cognition of and demand for medical statistics from January 2007 to July 2014 and conducted a meta-analysis of non-controlled studies with sub-group analysis for undergraduates, graduates, and medical staff.ResultsThere are substantial differences with respect to the cognition of theory in medical statistics among undergraduates (73.5%), graduates (60.7%), and medical staff (39.6%). The demand for theory in medical statistics is high among graduates (94.6%), undergraduates (86.1%), and medical staff (88.3%). Regarding specific statistical methods, the cognition of basic statistical methods is higher than of advanced statistical methods. The demand for certain advanced statistical methods, including (but not limited to) multiple analysis of variance (ANOVA), multiple linear regression, and logistic regression, is higher than that for basic statistical methods. The use rates of the Statistical Package for the Social Sciences (SPSS) software and statistical analysis software (SAS) are only 55% and 15%, respectively.ConclusionThe overall statistical competence of undergraduates, graduates, and medical staff is insufficient, and their ability to practically apply their statistical knowledge is limited, which constitutes an unsatisfactory state of affairs for medical statistics education. Because the demand for skills in this area is increasing, the need to reform medical statistics education in China has become urgent.     

Predictive value of metabolomic biomarkers for cardiovascular disease risk: a systematic review and meta-analysis

Abstract

Background: Metabolomic analysis aids in the identification of novel biomarkers by revealing the metabolic dysregulations underlying cardiovascular disease (CVD) aetiology. The aim of this study was to evaluate which metabolic biomarkers could add value for the prognosis of CVD events using meta-analysis.

Methods: The PRISMA guideline was followed for the systematic review. For the meta-analysis, biomarkers were included if they were tested in multivariate prediction models for fatal CVD outcomes. We grouped the metabolites in biological classes for subgroup analysis. We evaluated the prediction performance of models which reported discrimination and/or reclassification statistics.

Results: For the systematic review, there were 22 studies which met the inclusion/exclusion criteria. For the meta-analysis, there were 41 metabolites grouped into 8 classes from 19 studies (45,420 subjects, 5954 events). A total of 39 of the 41 metabolites were significant with a combined effect size of 1.14 (1.07–1.20). For the predictive performance assessment, there were 21 studies, 54,337 subjects, 6415 events. The average change in c-statistic after adding the biomarkers to a clinical model was 0.0417 (SE 0.008).

Conclusions: This study provides evidence that metabolomic biomarkers, mainly lipid species, have the potential to provide additional prognostic value. Current data are promising, although approaches and results are heterogeneous.     

Limitations of Poisson statistics in describing radioactive decay

ObjectivesThe assumption that nuclear decays are governed by Poisson statistics is an approximation. This approximation becomes unjustified when data acquisition times longer than or even comparable with the half-lives of the radioisotope in the sample are considered. In this work, the limits of the Poisson-statistics approximation are investigated.MethodsThe formalism for the statistics of radioactive decay based on binomial distribution is derived. The theoretical factor describing the deviation of variance of the number of decays predicated by the Poisson distribution from the true variance is defined and investigated for several commonly used radiotracers such as ¹⁸F, ¹⁵O, ⁸²Rb, ¹³N, ^99mTc, ¹²³I, and ²⁰¹Tl.ResultsThe variance of the number of decays estimated using the Poisson distribution is significantly different than the true variance for a 5-minute observation time of ¹¹C, ¹⁵O, ¹³N, and ⁸²Rb.ConclusionsDurations of nuclear medicine studies often are relatively long; they may be even a few times longer than the half-lives of some short-lived radiotracers. Our study shows that in such situations the Poisson statistics is unsuitable and should not be applied to describe the statistics of the number of decays in radioactive samples. However, the above statement does not directly apply to counting statistics at the level of event detection. Low sensitivities of detectors which are used in imaging studies make the Poisson approximation near perfect.     

拉曼光谱分析技术在资源微生物发酵性能评价中的应用

微生物发酵过程是细胞新陈代谢进行物质转化的过程,为了提高目标产物的转化率,需要对微生物发酵动态特性进行实时分析,以便实时优化发酵过程。拉曼光谱(Raman spectroscopy)量化测试作为一种有应用前景的在线过程分析技术,可以在避免微生物污染的条件下,实现精准监测,进而用于优化控制微生物发酵过程。【目的】以运动发酵单胞菌(Zymomonas mobilis)为例,建立微生物发酵过程中葡萄糖、木糖、乙醇和乳酸浓度拉曼光谱预测模型,并进行准确性验证。【方法】采用浸入式在线拉曼探头,收集运动发酵单胞菌发酵过程中多个组分的拉曼光谱,采用偏最小二乘法对光谱信号进行预处理和多元数据分析,结合离线色谱分析数据,对拉曼光谱进行建模分析和浓度预测。【结果】针对运动发酵单胞菌,首先实现拉曼分析仪对单一产品乙醇发酵过程的精准检测,其次基于多元变量分析,建立葡萄糖、乙醇和乳酸浓度变化的预测模型,实现对发酵过程中各成分浓度变化的准确有效分析。【结论】成功建立了一种评价资源微生物尤其是工业菌株发酵液多种组分的拉曼光谱分析方法。该方法为运动发酵单胞菌等工业菌株利用多组分底物工业化生产不同产物的实时检测,以及其他微生物尤其工业菌株的选育和过程优化提供了新方法。     

Extended jurisdiction and the management of Pacific highly migratory species

Abstract

The Pacific region is the most important producer of tropical tuna in the world. Three subregions account for the production: Pacific Latin America, the Pacific Islands region, and Southeast Asia. Prior to the UN Third Conference on the Law of the Sea, the Tuna Fisheries in the subregions were the preserve of developed distant water fishing nations. The situation has now been entirely reversed, with coastal state jurisdiction and control being realized in all three subregions. It is argued that American opposition to coastal state jurisdiction over tuna resources acted as a goad to the coastal states in Pacific Latin America and the Pacific Islands region in their quest for greater control over tuna resources. There are prospects of cooperation developing among the three Pacific subregional tuna producers. It is argued further that American action may have inadvertently accelerated the progress toward cooperation.     

A Comparison of Aggregate P-Value Methods and Multivariate Statistics for Self-Contained Tests of Metabolic Pathway Analysis

For pathway analysis of genomic data, the most common methods involve combining p-values from individual statistical tests. However, there are several multivariate statistical methods that can be used to test whether a pathway has changed. Because of the large number of variables and pathway sizes in genomics data, some of these statistics cannot be computed. However, in metabolomics data, the number of variables and pathway sizes are typically much smaller, making such computations feasible. Of particular interest is being able to detect changes in pathways that may not be detected for the individual variables. We compare the performance of both the p-value methods and multivariate statistics for self-contained tests with an extensive simulation study and a human metabolomics study. Permutation tests, rather than asymptotic results are used to assess the statistical significance of the pathways. Furthermore, both one and two-sided alternatives hypotheses are examined. From the human metabolomic study, many pathways were statistically significant, although the majority of the individual variables in the pathway were not. Overall, the p-value methods perform at least as well as the multivariate statistics for these scenarios.     

Evaluation of MLC performance in VMAT and dynamic IMRT by log file analysis

PurposeThis multi-institution study assessed the positioning accuracy of multileaf collimators (MLC) by analyzing log files. It determined the main machine parameters that affect MLC positioning errors for pre-TrueBeam (Clinac) and TrueBeam linacs.MethodsAround 30,000 dIMRT and VMAT log files belonging to 6 linacs from 4 different centers were analyzed. An in-house software was used to calculate 95th percentile and RMS error values and their correlation with certain parameters such as maximum leaf speed, mean leaf speed and gantry angle. The effect of MLC communication delay on error statistics was assessed in Clinac linacs. To that end MLC positioning error statistics were calculated with and without the delay effect.ResultsFor dIMRT treatments in Clinac linacs the mean leaf RMS error was 0.306 mm with and 0.030 mm without the delay effect. Leaf RMS error was closely linked to maximum and mean leaf speeds, but without the delay effect that link was weaker. No trend was observed between bank RMS error and gantry angle. Without the delay effect larger bank RMS errors were obtained for gantry angles with leaf movements against gravity. For VMAT treatments in TrueBeam linacs the mean leaf RMS error was 0.038 mm. A link was also observed between leaf RMS error and maximum and mean leaf speeds.ConclusionTrueBeam MLC positioning errors are substantially lower than those of Clinac linacs. In Clinac machines the analysis of dynalogs without the delay effect allows us to study the influence of factors that are masked by the delay effect.     

Inter- and intraspecific variation in grass phytolith shape and size: a geometric morphometrics perspective

Background and AimsThe relative contributions of inter- and intraspecific variation to phytolith shape and size have only been investigated in a limited number of studies. However, a detailed understanding of phytolith variation patterns among populations or even within a single plant specimen is of key importance for the correct taxonomic identification of grass taxa in fossil samples and for the reconstruction of vegetation and environmental conditions in the past. In this study, we used geometric morphometric analysis for the quantification of different sources of phytolith shape and size variation.MethodsWe used landmark-based geometric morphometric methods for the analysis of phytolith shapes in two extant grass species (Brachypodium pinnatum and B. sylvaticum). For each species, 1200 phytoliths were analysed from 12 leaves originating from six plants growing in three populations. Phytolith shape and size data were subjected to multivariate Procrustes analysis of variance (ANOVA), multivariate regression, principal component analysis and linear discriminant analysis.Key ResultsInterspecific variation largely outweighed intraspecific variation with respect to phytolith shape. Individual phytolith shapes were classified with 83 % accuracy into their respective species. Conversely, variation in phytolith shapes within species but among populations, possibly related to environmental heterogeneity, was comparatively low.ConclusionsOur results imply that phytolith shape relatively closely corresponds to the taxonomic identity of closely related grass species. Moreover, our methodological approach, applied here in phytolith analysis for the first time, enabled the quantification and separation of variation that is not related to species discrimination. Our findings strengthen the role of grass phytoliths in the reconstruction of past vegetation dynamics.     

Evolution And Historical Reductionism

Abstract

In response to Hoebel's criticism (1980) of the use of a dialectical model to interpret Cheyenne history, this article examines Hoebel's own views on kinship, politics, and social change. It is argued that Hoebel confuses descent with residence, and is committed to a methodology which necessarily gives inconclusive results. Most importantly, it is argued that Hoebel's theoretical perspective, characterized as “historical reductionism,” imposes a rigidly normative structure onto a society that was undergoing radical social change in the nineteenth century.     

A rhetorical discourse analysis of online anti-Muslim and anti-Semitic jokes

Abstract

Constructed with linguistic devices that resemble metaphor and other rhetorical devices, humour has the inbuilt ability to support racism in various readings. Through a discourse analysis of anti-Muslim and anti-Semitic jokes, this article outlines the connections between humorous and serious racism. It explains how online humour expresses two logics of racism: social inclusion and exclusion. Stereotypes and inferiorization are used in combination and separately to form ‘acceptable’ inclusive images in jokes. Where jokes depict exclusion, this is achieved through images of removal, violence or death. Although the stereotypes and exclusions of Muslims and Jews presented in the jokes are not the same, having both different histories and different trajectories in relation to contemporary racializations, it is argued that the underlying logic of racism is the same. This logic, in particular readings, supports the hard and extreme right-wing views of some of the websites, although the jokes are open to other interpretations as well.     

Effect of heterogeneous structure in mechanically unstressed biofilms on overall growth

In contrast to their name, biofilms are not always flat and homogeneous but instead often exhibit complex structural heterogeneity. It has been suggested that nonhomogeneous geometry is selected in order to increase biofilm growth rate. A previous study (Dockery and Klapper (2002) SIAM J. Appl. Math., 62, 853–869) of a model biofilm system in a static bulk fluid demonstrated that under some circumstances a flat biofilm-bulk fluid interface is linearly unstable to perturbation due to growth induced forces. Computations indicated that subsequent nonlinear evolution results in fingers and mushrooms of biofilm similar to structures observed in actual biofilms. However, the important complementary issue of biological functionality was not considered. Here a weakly nonlinear analysis of the simple growing biofilm layer model in Dockery and Klapper (2002, SIAM J. Appl. Math., 62, 853–869) is presented. It is argued that, at least in the case of biofilms free of external mechanical stress, overall growth is in fact generally inhibited by the presence of growing perturbations in the linear stage. Hence a more complex explanation of function is necessary.     

油藏样本潜在核心功能微生物群的宏基因组挖掘

【背景】识别出具有驱油功能的内源性微生物群是当前设计高效微生物采油技术的迫切需求。【目的】通过宏基因组分析找出原位油藏微生物中具有产酸/产气功能的潜在核心微生物群。【方法】利用室内模拟体系,对原位油藏微生物进行有机营养(从有氧到无氧)的激活,运用生物信息、多元统计分析以及网络分析等方法,寻找潜在内源性核心功能微生物群。【结果】有机营养激活了原位油藏样本中以Bacillus licheniformis为核心的产酸菌群(包括Coprothermobacter proteolyticus、Marinobacterspp.、Anaerobaculumhydrogeniformans和Petrotogamobilis),该菌群具有以丙酮酸/乙酰辅酶A为原料发酵乳酸、乙酸以及甲酸的功能;激活了以Enterococcus faecium为核心的产气菌群(包括Shinella zoogloeoides、Paracoccus denitrificans、Paracoccus spp.和Enterobacter cloacae),该菌群具备以(亚)硝酸盐、(亚)硫酸盐、石油烃为原料生产含氮/硫/碳等气体的能力。2个核心菌群内部分菌同时具有产酸和产气通路基因,激活过程中2个菌群的丰度变化呈负相关关系。【结论】利用有机营养激活体系及宏基因组测序分析技术,筛选出了油藏样本中具备产酸、产气能力的核心功能菌群,为后续进一步的功能菌株研究提供了潜在靶标及功能指向。